Device for the extraction of core samples

ABSTRACT

Described herein is a device useful for extraction of core samples from, e.g., muscle tissue of live animals and carcasses. The device is comprised of an extractor body sharpened at one end and hollow to receive a core cut by the sharpened end as it advances into sampled tissue, the forward end of the body being provided with a blade inwardly pivotally responsive to, e.g., muscle tissue backflow to sever the base of the core from surrounding tissue. The extractor is preferably affixed to thrust-generating means which withdraw the extractor body and contained core from sampled tissue when a predetermined degree of advance has occurred.

United States Patent 1151 3,683,892 Harris 14 1 Aug. 15, 1972 [54]DEVICE FOR THE EXTRACTION OF 3,175,554 3/1965 Stewart 128/2 B CORESAMPLES 3,001,522 9/1961 Silverman ..l28/2 B [721 memo" Roy "mis, Logan,Utah FOREIGN PATENTS OR APPLICATIONS 1 1 Assignw The BattelleDevelopment p 146 433 8/1962 U.S.S.R ..128/2 B tion, Columbus, Ohio 22 iJuly 13, 97 Primary Exlrjminesrl-iKyle L. Howell 211 App]. No.: 54,463Attorney v [57] ABSTRACT U.S. B, herein i a device useful for extractionf 51 I Cl 30/280 73/425 128/305 core samples from, e.g., muscle tissueof live animals I l i E 3 4 3 g and carcasses. The device is comprisedof an extractor 1 0 53 body sharpened at one end and hollow to receive al l 1 core cut by the sharpened end as it advances into sampled tissue,the forward end of the body being provided with a blade inwardlypivotally responsive to, [56] References Cited e.g., muscle tissuebackflow to sever the base of the UNITED STATES PATENTS cor?fglamaurrgutndiglg ttissue, "tithe extractoll'1 pre era y lxe o rus-genera mg means w 1c 1,609,456 12/1926 Boyle ..30/25 withdraw theextractor body and contained core from 1,509,858 9/1924 Boyle ..30/25Sampled tissue when a predetermined degree of 1,454,311 5/1923 Boyle..30/25 Vance has occurred 1,051,175 1/1913 Thompson ..30/25 X 3,512,5195/1970 Hall 128/2 B 6 Claims, 5 Drawing Figures msmznwmmz j/ ll/ I NVENTOR.

DEVICE FOR THE EXTRACTION OF CORE SAMPLES BACKGROUND OF THE INVENTIONPreviously, muscle tissue cores have been withdrawn from the carcassesof meatproducing animals for use in nutritional and food research.Consumer surveys have indicated that of the factors such as juiciness,aroma, flavor, and texture which contribute to the eatability of meatstenderness is the most important single attribute contributing to theacceptability of meat. Conventionally, tenderness is measured by resortto the well known Warner-Bratzler shear determination or alternatively,by submission of cooked meat samples to a tasting panel. In each case,the samples generally consist of one-half inch cubes of meat cooked toan internal temperature of 65 C. Correlation between sensory methods andthe Warner-Bratzler shear is generally in the range of 0.60 to 0.85,with an average value of about 0.75. When the variability within sensorypanels is considered, it becomes apparent that a correlation of thismagnitude is quite significant.

It has been proposed to determine the tenderness of rail-suspendedcarcasses by manually pressing probes into the carcass, the probesregistering resistance to entry on a strain gauge. Unlike the case ofshear determinations of tenderness of tissue cores, no significantcorrelation has been established between strain measurements and sensorydeterminations of tenderness. The aforementioned strain determination isalso unsatisfactory for tenderness determinations carried out on liveanimals because explosive force is required to penetrate the hide,whereupon the effect of the hide, fat layer, and the meat upon thestress readings must be isolated. Because tenderness and other meatquality characteristics are inheritable, tenderness determinationsconducted with live animals could be employed in on-the-hoof grading andselection of breeding stock. Similarly, tenderness determinations onlive animals could provide useful information to purchasers of cattleand other meat-producing animals. Absent significant correlation betweenstrain determinations made on raw meat and sensory or sheardeterminations on cooked samples, and generally in view of the currentstate of the art vis-a-vis sampling from live animals, the removal oftissue cores continues to offer the most like ly avenue to live animaltenderness evaluation. However, need has existed for core removal meanssuitable for expeditious sampling from large numbers of animals.

Prior art methods of extracting muscle tissue from live animals havebeen slow, inflicting pain, stress, and trauma to the animal andsubstantial risk to the operator. Those methods involve cutting a corewith either a knife, scalpel or coring tube, followed by manual severingof the tissue at the attached end and removal of the severed core fromthe wound. Even in the case where a carcass rather than a live animal issampled, severing the base of the tissue core has required anadditional, time-consuming step. Consequently, a need has and does existfor a means of removing tissue cores from carcasses and live animalswhich is capable of fast, trauma-free operation.

BRIEF SUMMARY OF THE INVENTION According to this invention there isprovided a tissue core extraction device comprising an extractor bodyhollow to receive a core cut by the terminal edge of the risk and stressand trauma to the animal heretofore experienced in live animal sampling.

Yet another object of the invention is to provide a means by which thebase of a tissue core can be severed without requiring a step separatefrom that employed to form the core itself.

A further object of the invention is to make possible large scale tissuesampling of live animals by a straightforward and efficient procedure.

These and other objects and advantages of the invention will becomeapparent from the more detailed description which follows, and from theattached drawing in which:

FIG. 1 is an exploded pictorial view of the core cutting and severingcomponents of one embodiment of the instant invention;

FIG. 2 is a partial sectioned view of a preferred thrust-generatingmechanism employed with the device of FIG. 1; and

FIGS. 3A, 3B,, and 3C sequentially illustrate the cutting action of apreferred embodiment of this invention.

DETAILED DESCRIPTION OF THE INVENTION:

With reference now to the FIG. 1 depiction of a preferred embodiment ofthe invention, the forward end of an extractor body 1 is provided with aterminal cutting edge 2. When driven forward in the direction indicatedby arrow in FIG. 1 into the longissimus dorsi, semitendinosus or othermuscle tissue of a meatproducing animal, a core is cut by the saidterminal edge and received within the hollow extractor body. Followingseverance of the base of the core by core severing means 3 andwithdrawal of the core-containing extractor body from the sampledcarcass or animal, the core is withdrawn from the extractor body bymeans of, e.g., core removal slot 4. Core severing means 3 is mounted inan opening 5 in a wall of the extractor body adjacent the forward endthereof in such fashion as to pivot inwardly about shaft 6, which latteris preferably journaled in opposed walls of extractor tional cocking andtriggering mechanisms (not shown) are employed to activate firing pin 8to strike and fire a .22 caliber blank cartridge held between chamberblock 9 and restraining block 10. The resulting explosion acts to urgepiston member 11 forward, compressing a series of rubber washers 12positioned about the piston between metal washers 13. Because the pistonis threadably attached to base block 7, which is in turn attached byscrews or other means to extractor body 1, the forward movement of thepiston 11 drives the extractor body forward as well. The throw or ex-.

tent of advance of the piston can be predetermined by appropriateadjustment of the length thereof, the number and type of rubber washersemployed, etc., as will be apparent to the art skilled. When thepredetermined degree of advance has occurred, the spring action of therubber washers causes the piston to retreat into its housing 14,whereupon the extractor body which is attached thereto similarlyretreats from the muscle tissue into which it has been forced by advanceof the piston. In light of the above, it will be apparent to the artskilledthat application of the advance-retreat principle exemplified bythe thrust-generating means depicted contributes to the efficiency ofcore removal operation with which this invention is concerned. Ofcourse, the invention can be employed in conjunction with otherthrust-generating means such as those in which a metal spring supplantsthe rubber washer arrangement illustrated in FIG. 2, other spring-loadedthrust-generating means, pneumatic or manual means, etc. Variousmodifications and refinements of the thrust-generating means will beapparent to the art skilled in light of this disclosure, e.g., thethrustgenerating means of FIG. 2 can be hinged between the chamber block9 and restraining block to permit ejection of spent cartridges, etc. I

The cutting action of the invented device is further discussed withreference to FIGS. 3A, 3B, and 3C, which sequentially depict advance andretreat of the forward end of the extractor body 1 and contained corebase-severing means 3 through muscle tissue. As the extractor bodyadvances, the terminal cutting edge 2 cuts and advances through a corechannel 15 forming a core which during the period of advance remainsattached to surrounding tissue at its base. When the extractor body 1has advanced to a predetermined degree, withdrawal of the extractor bodyfrom the core channel is commenced. At that point in time, the backflowof surrounding muscle tissue into the core channel and extractor bodyopening in which the core base severing blade is pivotally mountedcauses the severing blade to pivot inwardly into the extractor body, asshown in FIG. 3B. Tissue backflow, in combination with the forwardmovement of the core relative to the retreating extractor body causesthat pivoting action to continue until, preferably, the core basesevering blade is restrained from further rotation by the wall of theextractor body opposite that in which the core base severing blade 3 ismounted. That restraint can be provided simply by choosing the radius ofpivot r to be sufficiently greater than the inside width d of theextractor body 1 as to prevent rotation of the core base severing bladethrough 90. As shown in FIGS. 33 and 3C, the inward movement of the corebase severing blade causes the core to be severed at its base fromsurrounding muscle tissue. Once pivot of the core base severing bladehas been completed and further movement restrained by the extractor bodywall opposite that in which the blade is mounted, the blade serves toretain the severed core within the extractor body during withdrawal ofthat body from the core channel.

As depicted in the attached drawings, the terminal cutting edge andcutting edge of the core base severing blade are simply tapered to formknife edges. Alternatively, of course, the various cutting edges can beformed by sharpening in two planes, hollow grinding, etc. Extractorbodies employed to date have been formed from square stock so as toobtain cores suitable for preparation of the cubical samplesconventionally employed in sensory testing or Warner-Bratzler sheardeterminations of tenderness. Alternatively, of course, the extractorbody could be circular or ellipsoidal in cross section, etc. In everycase, of course, it is preferred that the core base severing blade beflushably fitted to the extractor body so as not to impede advance ofthe muscle tissue extractor into the tissue to be sampled. In thisconnection, it should be noted that the knife edge of the core basesevering blade can be beveled to mate with a recess 16 formed in therearward edge of the opening 5 in the extractor body wall in which theblade is mounted. Mating of the extractor body wall and core basesevering blade edge in that fashion permits rapid advance of theextractor body into the tissue to be sampled and at the same time servesto prevent fortuitous pivotal movement of the blade outside theextractor body. Thereby, the barb action which would otherwise obtainand hamper retreat of the extractor from the core channel is prevented.i

To date, backflow of muscle tissue has proved quite sufficient topromote inwardly pivotal movement of the base severing blade. Thatmovement can additionally be encouraged by provision of barbedprotuberances on the inner surface of the base severing blade or inother manners which will become apparent to the artskilled in light ofthe foregoing disclosure. For example, the dimension can be greater thanthe opening in the extractor body wall in which core base severing bladeis mounted. In this instance the cutting edge of the blade catches" thecore as it moves forward relative to the extractor body upon withdrawalof the instrument. The mechanical advantage to be gained by provision ofsuch supplemental means of promoting pivotal action must be balanced inevery case against the impediments to advance of the extractor bodycreated thereby, and to additional pain, trauma, or stress to thesampled animal which result therefrom.

In using the muscle tissue extractor of the invention,

the animal to be sampled is placed in a squeeze chute and identified byits number. The position for sampling is located and the hair clipped asclose to the skin as possible at that position. The position at whichthe incision is to be made is then disinfected and anesthetized.Anesthetization is preferably accomplished by placing a containerpartially filled with liquid nitrogen on the exposed skin forapproximately 20 seconds. The 20 second exposure renders the skinsufficiently insensitive as to permit incision and core extractionwithout damaging the skin, hair, or muscle tissue. Unduly short exposureto the liquid nitrogen results in insufficient anesthetization, whileunduly long exposure, e.g., in excess of about 25 seconds results infreezing of the skin so that cutting is more difficult. Care should beexercised to avoid contact of liquid nitrogen with the skin. Of course,anesthetization means other than liquid nitrogen can be employed,although that is the preferred course. Following anesthetization anincision is then made through the skin and fat layer. The length of theincision is dependent upon the size of the extractor body employed. Ifreasonable care is used, the animal usually displays no discomfort andremains calm in the chute. The extractor body is then gently placedthrough the skin incision and through the incision in the layer ofexternal fat. When the fat has been completely penetrated, thethrust-generating mechanism is triggered. The extractor bodyinstantaneously thrusts forward and cuts through the muscle. Aswithdrawal of the extractor body begins, the core base severing bladedrops down and severs the tissue core from surrounding tissue. Theextractor body with the contained core is then completely withdrawn. Thewound is medicated with a topical disinfectant and the animal turned outof the chute. The cored sample is removed from the extractor body with apair of forceps and deposited in a labeled container. Before furtheruse, the extractor body should be disinfected and the mechanism checkedto insure that no residue remains.

The invention is further illustrated with reference to the followingexample.

EXAMPLE An extractor body 3% inches in length and twentythree/thirty-twoinch square in cross section is formed from 4130 square tubing stock.The forward edge of the body is sharpened by A; inch taper to a knifeedge. A core base severing blade twenty-five/thirty-two inch in lengthby nineteen/thirty-two inch width is formed from 0.065 inch thick 4130sheet stock, sharpened at one end to form a cutting edge and tapped atthe opposite endto admit a shaft formed from 0.049 C/M wire. The shaftis employed to secure the cutting blade in an appropriately sized recessin the extractor body wall adjacent the terminal cutting edge thereof. ARemington Hand Stunner, Model No. 412 is modified to increase the throwpiston thereof to an appropriate length and the piston threadablyattached to a 75 inch square 7% inch thick base block formed from 1020stock and attached to the rearward end of the extractor body by fourscrews. When employed for core sampling, a muscle tissue extractor ofthe dimensions given above consistently yields a core 5.0 to 6.3 cm.long, approximately 1.78 cm. wide, and 1.02 cm. thick. Of course, thedimensions of the muscle tissue extractor are primarily determined bythe size of the particular sample desired.

Using a muscle tissue extractor like that described above, twoexperienced technicians performing the necessary surgical procedures,aided by three assistants, extracted longissimus dorsi muscle cores from10 animals in approximately 25 minutes. An incision from about 5.7 toabout 6.4 cm. in length is sufficient for a tissue extractor sodimensioned. Cores can be taken from both sides without apparent adverseeffect upon the animals, and second cores have been successfullyextracted adjacent the first where the space between the first andsecond coring position was not less than 6 cm. Most animals sampledshowed no reaction to the coring procedure. Little external bleedingoccurs and what little swelling is manifested starts receding by thethird or fourth day following core extraction. Twenty days after coreextraction the location of the incision can be only difficultyidentified, healing of the skin being practically complete. Carcasses ofanimals slaughteredfour days after tissue extraction show a slight slitin the fat cover where the incision was made. The lean muscle tissue hadclosed together, no open hole was visible, and the amount of bruisingwas slight. In most instances, the area displayed no more bruising thanthat which results from a typical grub infestation. In excess of 100extractions have been performed from bovine specimens, with but a singleresulting case of infection attributable to the coring procedure.

From the foregoing, it will be apparent that by the in- Y vention therehas been provided an efficient and trouble-free means of extractingtissue samples from live animals. Whether live animals or,alternatively, carcass tissue is sampled, the invention permits corebase severing without resort to the additional steps which haveheretofore been required. By the invention the animal suffering andoperator risk heretofore inherent in live animal sampling has beenminimized.

l claim:

1. A device for the extraction of core samples comprising an elongatedhollow extractor body having a terminal cutting edge on the forward endthereof, said extractor body being adapted to receive therewithin a corecut by said terminal edge, and severing means pivotally mounted in anopening in one wall of said extractor body adjacent the forward endthereof, said severing means extending from said pivotal mount in adirection away from said terminal cutting edge, said severing meanshaving a cutting edge opposite said pivotal mount and a length greaterthan the internal dimension of said extractor body and adapted to pivotinwardly from said wall into said extractor body upon withdrawal of saidextractor body from a core channel cut by said terminal edge, inresponse to backflow of material from which such core is cut, to severthe base of such core and retain the same within said extractor body tobe withdrawn with said extractor body, and means associated with saidbody to permit removal of such core sample.

2. The device of claim 1 which additionally comprises thrust-generatingmeans affixed to the rearward end of said body and adapted to drive saidbody forward with force sufficient to cut said core.

3. The device of claim 2 wherein said thrust generating means compriseadvance-retreat means adapted to automatically retreat when apredetermined degree of advance has occurred, whereby upon retreat thesaid body containing said core is withdrawn from said channel.

4. The device of claim 1 wherein the radius of pivot is such that saidsevering means is restrained by the opposite wall of said body frompivoting through 5. The device of claim 4 wherein said removal meanscomprises at least one core removal slot intermediate the severing meansand the rearward end of the body.

6. The device of claim 1 wherein the radius of pivot is such that therearward edge of said opening serves as a stop preventing pivoting ofsaid means outwardly of said body. I

1. A device for the extraction of core samples comprising an elongatedhollow extractor body having a terminal cutting edge on the forward endthereof, said extractor body being adapted to receive therewithin a corecut by said terminal edge, and severing means pivotally mounted in anopening in one wall of said extractor body adjacent the forward endthereof, said severing means extending from said pivotal mount in adirection away from said terminal cutting edge, said severing meanshaving a cutting edge opposite said pivotal mount and a length greaterthan the internal dimensiOn of said extractor body and adapted to pivotinwardly from said wall into said extractor body upon withdrawal of saidextractor body from a core channel cut by said terminal edge, inresponse to backflow of material from which such core is cut, to severthe base of such core and retain the same within said extractor body tobe withdrawn with said extractor body, and means associated with saidbody to permit removal of such core sample.
 2. The device of claim 1which additionally comprises thrust-generating means affixed to therearward end of said body and adapted to drive said body forward withforce sufficient to cut said core.
 3. The device of claim 2 wherein saidthrust generating means comprise advance-retreat means adapted toautomatically retreat when a predetermined degree of advance hasoccurred, whereby upon retreat the said body containing said core iswithdrawn from said channel.
 4. The device of claim 1 wherein the radiusof pivot is such that said severing means is restrained by the oppositewall of said body from pivoting through 90* .
 5. The device of claim 4wherein said removal means comprises at least one core removal slotintermediate the severing means and the rearward end of the body.
 6. Thedevice of claim 1 wherein the radius of pivot is such that the rearwardedge of said opening serves as a stop preventing pivoting of said meansoutwardly of said body.